It is often desirable to be able to alter the height of a support surface such as a table. It is especially important to be able to adjust the height of a massage table because if the table is too low the massage technician's back will be strained. However, if the table is too high the massage technician's applicable strength and range of movement will be restricted.
Accordingly, it is a standard feature on most massage tables to provide a height adjustment feature consisting of table legs with adjustable extension members. The leg and extension member are typically aligned in a parallel overlapping relationship along a tongue and groove interface. A series of holes are provided in either the leg or the extension member and a nut and bolt is used to lock the leg and extension member at the appropriate height.
A principle problem with standard height adjustable massage tables is that the required procedure for changing the height of the table is time consuming and cumbersome. Nuts and/or bolts on each table leg must be removed, repositioned into another hole and refastened. In the process of removing the bolt from the leg and extension member the two pieces, i.e., the leg and extension member, are susceptible to being completely separated. Further, there is no mechanism to assist with alignment of the holes after moving the extension member to its new position.
Others have proposed devices for simplifying table height adjustment. For example, U.S. Pat. No. 806,485, issued to Parker in 1905, discloses a height adjustable table in which a table leg and extension member are moveable relative to each other. The leg and extension member are bound by two yokes. The upper most yoke has a lever for allowing release of the yoke so that the locking serrations between the leg and extension member can be disengaged, allowing the height of the table to be altered. However, there are several notable problems with Parker's table. First, the serrations between the leg and extension member make it difficult to adjust or slide the extension member relative to the leg, particularly when lowering the height of the table. Second, Parker's mechanism requires two yokes to keep the leg and extension member parallel. A single yoke binding mechanism would be easier to manufacture and use.
Accordingly, it is an object of the present invention to produce a height adjustable table with a quick release clamp for easy and rapid height adjustment.
Another object is to produce a height adjustable table which only requires a single clamp per leg.
Another object is to provide a height adjustable table which allows easy relative movement between the leg and extension member when the clamp is in the unlocked position.
Another object is to provide a height adjustable table which allows adjustment between a leg and extension member without completely separating the two pieces.
Another object is to provide a height adjustment device which is suitable for use in a collapsible portable massage table for easy transfer or storage.